The present invention relates to a new and useful tubular clamping assembly for porviding an effective clamping force through the use of a unique lever and fulcrum structure. The present invention further includes a novel locking mechanism for preventing accidental disengagement of the clamping assembly.
Problems confronting known tubular clamping assemblies adaptable for use in the medical field include a constant clamping pressure required during the securing of a tubular member and inadvertent release of the secured clamping assembly. As an example, U.S. Pat. No. 3,629,912 issued Dec. 28, 1971 to Klopp is typical of the known prior art and suggests a clamping assembly which requires full clamping pressure to be continuously exerted during the clamping procedure, resulting in increased operator fatigue as well as increased difficulty in locking the clamping arms together. In comparison, applicant's invention employs a lever and fulcrum to develop a mechanical advantage which maintains the clamping arms in a semi-closed position with little operator pressure being required. This allows for a quick actuation as well as a much easier locking procedure.
Furthermore, the ball and socket locking mechanism of Klopp is susceptible to premature failure, in that the socket must be expanded during each engagement of the clamping assembly, resulting in the gradual deformation of the socket leading to premature disengagement of the clamping assembly.
A further example of the prior art in U.S. Pat. No. 3,942,228 issued March 9, 1976 to Buckman et al and suggesting a clamping assembly adaptable for pinching off a tubular member supported therebetween. It is further noted, that the clamping assembly in Buckman is retained in the engaged position entirely by frictional pressure. As with Klopp, the full clamping force in Buckman must be maintained during the entire actuation of the clamping assembly. Also, because a compressive clamping force must be continuously generated by the operator, the total force may not always be sufficient to ensure that fluid is continuously blocked from passing through the tubular member. Furthermore, the frictional locking mechanism in Buckman et al also has a greater susceptibility to inadvertent separation resulting from the gradual deformation of the clamping arm.
As will be discussed in detail hereinafter, an embodiment of applicant's invention overcomes the problem of an operator being required to supply a continuous clamping force, through the constant clamping force created by the unique lever and fulcrum clamping structure. An embodiment of the present invention also overcomes the problem of inadvertent clamp release by having a portion of one of the clamping arms extend through a hole formed in a flange attached to the opposite clamping arm.
While the present invention may be adaptable for use in the medical field to clamp endotracheal and similar tubular members, the present invention should not be limited to use as a medical clamp. Rather, the present invention may conveniently be used wherever a clamping assembly is considered.